Effects of Lower Body EMS Training in Postmenopausal Women (LB-EMS-PMW)

Effects of Lower-Body Electrical Muscle Stimulation Combined With Resistance Training on Body Composition, Muscle Function, and Arteriosclerosis-related Markers in Postmenopausal Women: A Three-arm Randomized Controlled Trial

This study evaluates the effects of a 8-week lower body Electrical Muscle Stimulation (EMS) training program on body composition, muscle function, and arteriosclerosis markers in postmenopausal women.

Menopause is associated with a rapid decline in estrogen, which increases the risk of sarcopenia (muscle loss) and arterial stiffness (cardiovascular disease). While resistance training is effective for these conditions, participation rates among postmenopausal women are often low. This study investigates whether applying EMS during lower body resistance exercises provides superior benefits compared to resistance training alone or no intervention.

Participants will be randomized into three groups:

1. Lower-body EMS combined with Resistance Training Group
2. Resistance Training Only Group
3. Control Group (No intervention)

The study aims to verify the efficacy of EMS as a time-efficient and effective alternative exercise modality for improving vascular and musculoskeletal health in this population.

Study Overview

• Status: Active, not recruiting
• Conditions: Arteriosclerosis; Body Composition; Sarcopenia; Muscle Function; Postmenopausal Women; Arterial Stiffness, Blood Pressure
• Intervention / Treatment: Device: Lower-body Electromyostimulation (LB-EMS) device; Behavioral: Lower Body Resistance Training

• Study Type: Interventional
• Enrollment (Actual): 38
• Phase: Not Applicable

Contacts and Locations

Study Locations

• South Korea
  • Seoul
    • Seoul, Seoul, South Korea, 08826
      • Seoul National University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Post-menopausal women (defined as cessation of menstruation for at least 12 months).
• Aged between 50 and 70 years.
• Sedentary lifestyle (no participation in regular resistance training programs within the last 6 months).
• Able to perform lower body resistance exercise with LB-EMS suit.
• Willing to participate in the study and provide informed consent.

Exclusion Criteria:

• Contraindications for WB-EMS: Presence of implanted electrical devices (e.g., pacemakers, defibrillators), severe bleeding disorders (e.g., hemophilia), abdominal/inguinal hernia, or history of surgery within the last 6 months (including stent insertion).
• Severe Chronic Diseases: Diagnosis of severe cardiovascular (e.g., MI, heart failure, arrhythmia), renal, neurological (e.g., epilepsy), or oncological diseases (currently undergoing treatment).
• Uncontrolled Cardiovascular Conditions: Uncontrolled hypertension or severe arterial circulatory disorders.
• Confounding Medications: Current use of hormone replacement therapy (HRT) for menopause or medications for severe psychiatric disorders (e.g., depression, anxiety).
• Acute Conditions & Others: Acute infection/inflammation, influence of alcohol/drugs, or any other condition deemed unsuitable by the investigator.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Resistance Training Only Group; Participants perform the identical lower body resistance training program without EMS stimulation. The session structure (10-min warm-up, 30-min main exercise, 10-min cool-down) and total duration (50 minutes) are the same as the experimental group.	Behavioral: Lower Body Resistance Training; A 50-minute session consisting of a 10-minute warm-up, 30 minutes of main lower body resistance training (4 types of machine-based exercises per session), and a 10-minute cool-down
No Intervention: Control Group; Participants maintain their usual daily lifestyle without engaging in any new exercise programs during the 6-week study period.
Experimental: Lower Body EMS + Resistance Training Group; Participants perform lower body resistance training while wearing a lower body EMS suit. Each session lasts 50 minutes (10-min warm-up, 30-min main exercise, 10-min cool-down). EMS stimulation is applied exclusively during the 30-minute main exercise phase (85Hz, 350µs). This program is conducted twice a week for 8 weeks.	Device: Lower-body Electromyostimulation (LB-EMS) device; Electrical stimulation applied to the lower body muscles (85Hz, 350µs) during the main exercise phase; Behavioral: Lower Body Resistance Training; A 50-minute session consisting of a 10-minute warm-up, 30 minutes of main lower body resistance training (4 types of machine-based exercises per session), and a 10-minute cool-down

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Body Fat Percentage	Assessed using BIA. The proportion of fat mass relative to total body weight. Unit of Measure: %	Baseline and Week 8

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Highest Brachial-ankle Pulse Wave Velocity (baPWV)	An indicator of arterial stiffness. Higher values indicate stiffer arteries. Unit of Measure: cm/s	Baseline and Week 8
Peak Torque (Knee Extension/Flexion) per body weight	The maximum torque produced during isokinetic knee extension and flexion. Assessed at a 60°/s angular velocity. Unit of Measure: Nm (Newton-meters)/kg	Baseline and Week 8
Skeletal Muscle Mass	Assessed using Bioelectrical Impedance Analysis (BIA). Represents the total weight of muscle tissue attached to the skeleton. Unit of Measure: kg	Baseline and Week 8
Total Body Fat Mass	Assessed using BIA. Represents the total weight of adipose tissue in the body. Unit of Measure: kg	Baseline and Week 8
Skeletal Muscle Mass Index (SMI)	Calculated as appendicular skeletal muscle mass (ASM) divided by height squared (kg/m^2). Used to assess sarcopenia status. Unit of Measure: kg/m^2	Baseline and Week 8
Waist Circumference	Measured at the midpoint between the lowest rib and the iliac crest using a standard anthropometric tape, with the participant standing and breathing normally. Unit of Measure: cm	Baseline and Week 8
Waist-to-Hip Ratio (WHR)	Calculated as waist circumference divided by hip circumference. An indicator of central adiposity and cardiometabolic risk. Unit of Measure: ratio	Baseline and Week 8
Estimated Visceral Fat Area (eVFA)	Assessed using BIA. Represents the cross-sectional area of visceral adipose tissue surrounding the abdominal organs. Unit of Measure: cm^2	Baseline and Week 8
Average Brachial-ankle Pulse Wave Velocity (baPWV)	An indicator of arterial stiffness. Average values indicate stiffer arteries. Unit of Measure: cm/s	Baseline and Week 8
Ankle-Brachial Index (ABI)	The Ankle-Brachial Index (ABI) is the ratio of the systolic blood pressure measured at the ankle to the systolic blood pressure measured at the brachial artery. It is a non-invasive indicator used to assess the presence and severity of peripheral arterial stenosis or occlusion. Lower ABI values (typically < 0.9) suggest narrowing or blockage of the arteries in the legs. Unit of Measure: ratio	Baseline and Week 8
Systolic Blood Pressure (SBP)	Measured using an automated oscillometric device after at least 5 minutes of seated rest. Represents the peak arterial pressure during ventricular contraction. Unit of Measure: mmHg	Baseline and Week 8
Diastolic Blood Pressure (DBP)	Measured using an automated oscillometric device after at least 5 minutes of seated rest. Represents the minimum arterial pressure during ventricular relaxation. Unit of Measure: mmHg	Baseline and Week 8
Pulse Pressure (PP)	The difference between systolic and diastolic blood pressure. It is a marker of arterial stiffness. Unit of Measure: mmHg	Baseline and Week 8
Mean Arterial Pressure (MAP)	Calculated as (SBP + 2 × DBP) / 3. Represents the average arterial pressure during one cardiac cycle. Unit of Measure: mmHg	Baseline and Week 8
Total Work Done per body weight	The total amount of work performed by the muscle groups during the test protocol(Knee extension/flexion) at an angular velocity of 180°/s. Unit of Measure: Nm/kg	Baseline and Week 8

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Fatigue Index	The percentage decline in peak torque calculated from the difference between the initial and final repetitions during a set of isokinetic contractions performed at an angular velocity of 180°/s. Unit of Measure: %	Baseline and Week 8
Hamstring-Quadriceps Ratio (H/Q Ratio)	The ratio of the peak torque of the hamstring muscles to the peak torque of the quadriceps muscles measured at an angular velocity of 60°/s. Unit of Measure: ratio	Baseline and Week 8
Bilateral Deficit	The percentage difference between the sum of peak torques produced by each leg individually and the peak torque produced when both legs act simultaneously, measured at an angular velocity of 60°/s. Unit of Measure: %	Baseline and Week 8

Collaborators and Investigators

• Sponsor: Seoul National University
• Investigators: Principal Investigator: Yeon Soo Kim, MD, Seoul National University

Study record dates

Study Major Dates

• Study Start (Actual): December 26, 2025
• Primary Completion (Estimated): June 12, 2026
• Study Completion (Estimated): June 26, 2026

Study Registration Dates

• First Submitted: January 23, 2026
• First Submitted That Met QC Criteria: January 30, 2026
• First Posted (Actual): February 4, 2026

Study Record Updates

• Last Update Posted (Actual): May 27, 2026
• Last Update Submitted That Met QC Criteria: May 22, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: Body Composition; Resistance Training; Vascular Health; Postmenopausal Women; Muscle Function; EMS; Electrical Muscle Stimulation
• Additional Relevant MeSH Terms: Neurologic Manifestations; Nervous System Diseases; Vascular Diseases; Cardiovascular Diseases; Neuromuscular Manifestations; Pathological Conditions, Anatomical; Arterial Occlusive Diseases; Muscular Atrophy; Atrophy; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Sarcopenia; Arteriosclerosis
• Other Study ID Numbers: IRB No. 2601/002-017

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No